• Title/Summary/Keyword: $R_m$

Search Result 16,544, Processing Time 0.044 seconds

DING INJECTIVE MODULES OVER FROBENIUS EXTENSIONS

  • Wang, Zhanping;Yang, Pengfei;Zhang, Ruijie
    • Bulletin of the Korean Mathematical Society
    • /
    • v.58 no.1
    • /
    • pp.217-224
    • /
    • 2021
  • In this paper, we study Ding injective modules over Frobenius extensions. Let R ⊂ A be a separable Frobenius extension of rings and M any left A-module, it is proved that M is a Ding injective left A-module if and only if M is a Ding injective left R-module if and only if A ⊗R M (HomR(A, M)) is a Ding injective left A-module.

Role of Glucocorticoids in Fasting-induced Changes in Hypothalamic and Pituitary Components of the Growth Hormone (GH)-axis

  • Kim, Eun-Hee;Seo, Sang-Hee;Chung, Hyun-Ju;Park, Seung-Joon
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.12 no.5
    • /
    • pp.217-223
    • /
    • 2008
  • To directly test if elevated glucocorticoids are required for fasting-induced regulation of growth hormone (GH)-releasing hormone (GHRH), GHRH receptors (GHRH-R) and ghrelin receptors (GHS-R) expression, male rats were bilaterally adrenalectomized or sham operated. After 7 days, animals were fed ad libitum or fasted for 48 h. Bilateral adrenalectomy increased hypothalamic GHRH to 146% and decreased neuropeptide Y (NPY) mRNA to 54% of SHAM controls. Pituitary GHRH-R and GHS-R mRNA levels were decreased by adrenalectomy to 30% and 80% of shamoperated controls. In shamoperated rats, fasting suppressed hypothalamic GHRH (49%) and stimulated NPY (166%) mRNA levels, while fasting increased pituitary GHRH-R (391%) and GHS-R (218%) mRNA levels. However, in adrenalectomized rats, fasting failed to alter pituitary GHRH-R mRNA levels, while the fasting-induced suppression of GHRH and elevation of NPY and GHS-R mRNA levels remained intact. In fasted adrenalectomized rats, corticosterone replacement increased GHRH-R mRNA levels and intensified the fasting-induced decrease in GHRH, but did not alter NPY or GHS-R response. These data suggest that elevated glucocorticoids mediate the effects of fasting on hypothalamic GHRH and pituitary GHRH-R expression, while glucocorticoids are likely not the major determinant in fasting-induced increases in hypothalamic NPY and pituitary GHS-R expression.

Comparison of physical fitness according to body mass index of Chinese college students (중국 대학생의 체질량지수에 따른 체력 비교)

  • Chen, Fu;Kim, Jung-Hyun;Kim, Ok-ja
    • Journal of Korean Physical Therapy Science
    • /
    • v.28 no.3
    • /
    • pp.53-65
    • /
    • 2021
  • Background: The purpose of this study was to a comparison of physical fitness according to the body mass index (BMI) of Chinese college students. Design: Cross-sectional study. Methods: According to the BMI, the research objects are divided into four types: underweight, normal weight, overweight, and obesity. This research took 26,976 college students who participated in Jiujiang College. It examines BMI, 50m, vital capacity, standing long jump, sitting forward bend, sit-up (female), pull-up (male), 800m (female), 1000m (male) which is to research the correlation between different BMI and other indicators. Results: The physical qualities of students with normal weight are significantly better than those with other BMI groups. Pearson correlation analysis showed that male BMI was positively correlated with vital capacity (r=0.07, p<0.01), 50m (r=0.15, p<0.01) and 1000m (r=0.14, p<0.01), and negatively correlated with standing long jump (r=-0.12, p<0.01), sitting forward bend (r=-0.06, p<0.01) and pull-up (r=-0.13, p<0.01); Female BMI was positively correlated with vital capacity (r=0.03, p<0.01), 50m (r=0.21, p<0.01) and 800m (r=0.18, p<0.01), and negatively correlated with standing long jump (r=-0.07, p<0.01), sitting forward bend (r=-0.11, p<0.01) and sit-up (r=-0.10, p<0.01). Conclusion: Overweight and underweight will affect the physical quality of college students. Students should keep their BMI within the normal range for their health.

R.M과 R.M 운동

  • U, Mu
    • 방재와보험
    • /
    • s.55
    • /
    • pp.56-59
    • /
    • 1992
  • 본 논문은 미국의 Kalin Tuan이 발표한 "1950~1985년간의 Risk manager와 Risk management(R.M) 운동" 으로서 제1장 Risk management 운동의 등장, 제2장 경영학의 교육과정으로서의 Risk management로 구성되어 있다. 본고에서는 제1장의 내용을 요약 소개하고자 한다.

  • PDF

R-(-)-TNPA, a Dopaminergic $D_2$ Receptor Agonist, Inhibits Catecholamine Release from the Rat Adrenal Medulla

  • Hong, Soon-Pyo;Seo, Hong-Joo;Lim, Dong-Yoon
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.10 no.5
    • /
    • pp.273-282
    • /
    • 2006
  • The aim of the present study was to investigate the effects of R-(-)-2,10,11-trihydroxy-N-propylnoraporphine [R-(-)-TNPA], a selective agonist of dopaminergic $D_2$ receptor and S(-)-raclopride, a selective antagonist of dopaminergic $D_2$ receptor, on the secretion of catecholamines (CA) evoked by cholinergic stimulation and membrane-depolarization in the isolated perfused model of the rat adrenal gland, and also to establish its mechanism of action. R-(-)-TNPA $(10{\sim}100\;{\mu}M)$ perfused into an adrenal vein for 60 min produced dose- and time-dependent inhibition in CA secretory responses evoked by ACh (5.32 mM), high $K^+$ (56 mM), DMPP $(100\;{\mu}M)$ and McN-A-343 $(100\;{\mu}M)$. R-(-)-TNPA itself did also fail to affect basal CA output. Also, in adrenal glands loaded with R-(-)-TNPA $(30\;{\mu}M)$, the CA secretory responses evoked by Bay-K-8644 $(10\;{\mu}M)$, an activator of L-type $Ca^2+$ channels and cyclopiazonic acid $(10\;{\mu}M)$, an inhibitor of cytoplasmic $Ca^{2+}-ATPase$ were also inhibited. However, S(-)-raclopride $(1{\sim}10\;{\mu}M)$, given into an adrenal vein for 60 min, enhanced the CA secretory responses evoked by ACh, high $K^+$, DMPP and McN-A-343 only for the first period (4 min), although it alone has weak effect on CA secretion. Moreover, S(-)-raclopride $(3.0\;{\mu}M)$ in to an adrenal vein for 60 min also augmented the CA release evoked by BAY-K-8644 and cyclopiazonic acid only for the first period (4 min). However, after simultaneous perfusion of R-(-)-TNP A $(30\;{\mu}M)$ and S(-)-raclopride $(3.0\;{\mu}M)$, the inhibitory responses of R(-)-TNPA $(30\;{\mu}M)$ on the CA secretion evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644, and cyclopiazonic acid were significantly reduced. Taken together, these experimental results suggest that R-(-)-TNPA greatly inhibits the CA secretion from the perfused rat adrenal medulla evoked by cholinergic stimulation (both nicotininc and muscarinic receptors) and membrane depolarization, but S(-)-raclopride rather enhances the CA release by them. It seems that this inhibitory of R-(-)-TNPA may be mediated by stimulation of inhibitory dopaminergic $D_2$ receptors located on the rat adrenomedullary chromaffin cells, while the facilitatory effect of S(-)-raclopride is due to the blockade of dopaminergic $D_2$ receptors, which are relevant to extra- and intracellular calcium mobilization. Therefore, it is thought that dopaminergic $D_2$ receptors may be involved in regulation of CA release in the rat adrenal medulla.

UNDERWATER DISTRIBUTION OF VESSEL NOISE (선박소음의 수중분포에 관한 연구)

  • PARK Jung Hee
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.10 no.4
    • /
    • pp.227-235
    • /
    • 1977
  • The noise pressure scattered underwater on account of the engine revolution of a pole and liner, Kwan-Ak-San(G. T. 234.96), was measured at the locations of Lat. $34^{\circ}47'N$, Long. $128^{\circ}53'E$ on the 16th of August 1976 and Lat. $34^{\circ}27'N$, Long. $128^{\circ}23'E$ on the 28th of July, 1977. The noise pressure passed through each observation point (Nos. 1 to 5), which was established at every 10m distance at circumference of outside hull was recorded when the vessel was cruising and drifted. In case of drifting, the revolution of engine was fixed at 600 r. p. m. and the noise was recorded at every 10 m distance apart from observation point No. 3 in both horizontal and vertical directions with $90^{\circ}$ toward the stern-bow line. In case of cruising, the engine was kept in a full speed at 700 r.p.m. and the sounds passed through underwater in 1 m depth were also recorded while the vessel moved back and forth. The noise pressure was analyzed with sound level meter (Bruel & Kjar 2205, measuring range 37-140 dB) at the anechoic chamber in the Institute of Marine Science, National Fisheries University of Busan. The frequency and sound waves of the noise were analyzed in the Laboratory of Navigation Instrument. From the results, the noise pressure was closely related to the engine revolution shelving that the noise pressure marked 100 dB when .400 r. p. m. and increase of 100 r. p. m. resulted in 1 dB increase in noise pressure and the maximum appeared at 600 r. p. m. (Fig.5). When the engine revolution was fixed at 700 r. p. m., the noise pressures passed through each observation point (Nos. 1 to 5) placed at circumference of out side hull were 75,78,76,74 and 68 dB, the highest at No.2, in case of keeping under way while 75,76,77,70 and 67 dB, the highest at No.3 in case of drifting respectively (Fig.5). When the vessel plyed 1,400 m distance at 700 r.p.m., the noise pressure were 67 dB at the point 0 m, 64 dB at 600m and 56 dB at 1,400m on forward while 72 at 0 m, 66 at 600 m and 57 dB at 1,400 m on backward respectively indicating the Doppler effects 5 dB at 0 m and 3 dB at 200 m(Fig.6). The noise pressures passed through the points apart 1,10,20,30,40 and 50 m depth underwater from the observation point No.7 (horizontal distance 20 m from the point No.3) were 68,75,62,59,55 and 51 dB respectively as the vessel was being drifted maintaining the engine revolution at 600 r. p. m. (Fig. 8-B) whereas the noise pressures at the observation points Nos.6,7,8,9 and 10 of 10 m depth underwater were 64,75,55,58,58 and 52 dB respectively(Fig.8-A).

  • PDF

Why Does m-Methyl Substituted Pesticides Show Higher Insecticidal Activity? On the Phenyl N-methylcarbamate and m-xylyl-N-methylcarbamate Derivatives (왜 m-methyl 치환 살충제들은 강한 살충작용을 나타낼까? -Phenyl N-methylcarbamate와 m-xylyl-N-methylcarbamate 유도체들에 관하여-)

  • Sung, Nack-Do
    • Applied Biological Chemistry
    • /
    • v.32 no.2
    • /
    • pp.170-177
    • /
    • 1989
  • In order to seek the molecular basis of higher insecticidal activity of the carbamates with two methyl groups, m-xylyl-N-methylcarbamate(MXNMC) than the corresponding unsubstituted phenyl N-methylcarbamate(PNMC), these two derivatives have been studied by molecular orbital(MO) theoretically using extended $H\ddot{u}ckel$ theory(EHT), and analysis of regression and linear free energy relationship(LFER). The most stable stereo structure(Z, Z) shows that the phenyl group occupies vertical(${\theta}=90^{\circ}$) position on the plane of the N-methylcarbamyl group. Regression analysis shows that especially good correlation exists between the $pI_{50}$ values and the calculated MO quantities when the hydrogen atomic charge of metaposition and of m-methyl groups, and LUMO energy are taken as variables. The LFER analysis on the carbamylation indicates that field(F) effect(60%) is slightly larger than resonance(R) effect(40%) in PNMC(E>R), whereas, in case of MXNMC, R effect(98.6%) is much larger than F effect(1.4%)($R{\gg}F$). From the basis on the findings, the enhancement of insecticidal activity of MXNMC may be the result of hyperconjugation by m-methyl groups.

  • PDF

Fragmentation Analysis of rIAPP Monomer, Dimer, and [MrIAPP + MhIAPP]5+ Using Collision-Induced Dissociation with Electrospray Ionization Mass Spectrometry

  • Kim, Jeongmo;Kim, Ho-Tae
    • Mass Spectrometry Letters
    • /
    • v.12 no.4
    • /
    • pp.179-185
    • /
    • 2021
  • Collision-induced dissociation (CID) combined with electrospray ionization mass spectrometry (ESI-MS) was used to obtain structural information on rat islet amyloid polypeptide (rIAPP) monomers (M) and dimers (D) observed in the multiply charged state in the MS spectrum. MS/MS analysis indicated that the rIAPP monomers adopt distinct structures depending on the molecular ion charge state. Peptide bond dissociation between L27 and P28 was observed in the MS/MS spectra of rIAPP monomers, regardless of the monomer molecular ion charge state. MS/MS analysis of the dimers indicated that D5+ comprised M2+ and M3+ subunits, and that the peptide bond dissociation process between the L27 and P28 residues of the monomer subunit was also maintained. The observation of (M+ b27)4+ and (M+ y10)3+ fragment ions were deduced to originate from the two different D5+ complex geometries, the N-terminal and C-terminal interaction geometries, respectively. The fragmentation pattern of the [MrIAPP + MhIAPP]5+ MS/MS spectrum showed that the interaction occurred between the two N-terminal regions of MrIAPP and MhIAPP in the heterogeneous dimer (hetero-dimer) D5+ structure.

Characterization of Tetracycline-Resistant Genes of Staphylococci isolates from Human and Marine Environment (사람과 해양환경에서 분리된 Staphylococci의 Tetracycline 내성 유전자의 특성 비교)

  • CHO, Ki-Taek;KIM, Young-Chul;KWON, Woo-Ju;JEONG, Hyun-Do
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.28 no.1
    • /
    • pp.59-68
    • /
    • 2016
  • For comparison of tetracycline-resistant ($Tc^R$) genes, we obtained 21 and 14 $Tc^R$ Staphylococcus spp. from marine environment and human patient, respectively. Although all isolates from human were identified as Staphylococcus aureus, higher proportion of $Tc^R$ isolates (12 out of 14) from human were utilizing tet(M) gene compared to that of $Tc^R$ isolates (6 out of 21) from marine environment. Additionally, collaborated utilization of tet(M) and erm(A) in $Tc^R-Em^R$ S. aureus in human patient, but not in $Tc^R$ Staphylococcus spp. isolates from marine environment was also characterized. Based on the nucleotide sequence of transposon related to $Tc^R$ gene, we confirmed the origin of tet(M) gene in $Tc^R$ Staphylococci isolated from marine environments and human are derived from Tn916/1545-like and Tn5801 transposon, respectively. It is the first report showing the presence of Tn5801 in all $Tc^R$ S. aureus carrying tet(M) in human patient. Alignment of the fully sequenced tet(M) from marine environmental isolates was also agreed with the determined transposons by showing the genomic mosaic structure composed with three genomic parts from Tn916/1545 and unknown transposons. Genetic characteristics of these tet(M) in environmental isolates were similar to each other but different from those in isolates from human showing only tet(M) from Tn916/5801 type. It may imply the presence of less dramatic communication of antibiotic resistant genes between Staphylococci isolated from marine environment and human.